ARM CPU memory latency monitor device

arm-memlat-mon is a device that represents the use of the PMU in ARM cores
to measure the parameters for latency driven memory access patterns.

Required properties:
- compatible:			Must be "qcom,arm-memlat-mon"
- qcom,cpulist:			List of CPU phandles to be monitored in a cluster
- qcom,target-dev:		The DT device that corresponds to this master port

Example:
	qcom,arm-memlat-mon {
		compatible = "qcom,arm-memlat-mon";
		qcom,cpulist = <&CPU0 &CPU1>;
		qcom,target-dev = <&memlat0>;
	};